Induction of Pulmonary Thromboembolism by Neutrophil Elastase in Collagen-Induced Arthritis Mice and Effect of Recombinant Human Soluble Thrombomodulin

Abstract

We previously reported that during total knee arthroplasty in rheumatoid arthritis (RA) patients, the use of tourniquet might promote local release of neutrophil elastase (NE) from neutrophils, which may contribute to the development of pulmonary thromboembolism (PTE) and tissue injury. The aim of this study was to develop PTE by the use of NE in a mouse model of collagen-induced arthritis (CIA) and investigate the relationship between thrombus and endothelial cells as well as the effect of recombinant human soluble thrombomodulin (rhs-TM) in reducing the risk of PTE. Male DBA/1J mice were injected intracutaneously at several sites with an emulsion containing bovine collagen and later a booster shot to produce CIA mice. Subsequently, NE was injected intravenously 2 times a day for 3 days and after a further 4 days, mice were sacrificed. A group of mice received rhs-TM injections prior to NE injections. We divided the mice into four groups of normal, CIA control, CIA + NE, and CIA + rhs-TM + NE mice and evaluated thrombus formation status. All CIA + NE mice developed PTE. In contrast, no thrombosis was found in normal control, CIA control and CIA + rhs-TM + NE mice. Plasma thrombin level, fibrinogen expression and neutrophil count were increased in CIA + NE mice. Double staining for anticoagulant TM and procoagulant von Willebrand factor (vWF) in pulmonary endothelial cells in normal mice showed a TM-dominant expression while in both CIA control and CIA + NE mice a vWF-dominant expression compatible with coagulant status was observed. Injection of rhs-TM into CIA + NE mice resulted in a phenotypic conversion of endothelial cells from vWF-dominant to TM-dominant expression and a reduction in fibrinogen deposition. These findings demonstrate that by repeated use of NE in CIA mice, it is feasible to produce PTE and to study its pathogenesis and that rhs-TM reduces the risk of PTE. We suggest that in surgical operations of upper and lower extremities in RA patients, the use of a tourniquet should be avoided as it may trigger NE release.

Does Minimally Invasive Total Knee Arthroplasty Improve Isokinetic Torque?

“…We found prolonged tourniquet and operating times for MIS TKAs, which is in agreement with other publications [11,24,25,27,37]. Therefore, we assume that the published risks and disadvantages of a tourniquet [3,28,34,42,43] could be more pronounced for MIS TKA.…”

Pulmonary inflammation in mice with collagen‐induced arthritis is conditioned by complete Freund's adjuvant and regulated by endogenous IFN‐γ

“…Although pulmonary complications commonly occur in RA patients, involvement of the lungs in animal models of RA is poorly documented. One report [9] described increased numbers of cells in BALFs in DBA/1 mice with CIA, whereas another study [12] failed to show any histopathological lung abnormality. In the present study of CIA in DBA/1 mice, we found that, in addition to their joint lesions, the animals also showed a variable degree of pulmonary involvement.…”

“…The pleura and the airways, as well as the interstitium and vasculature of the lung can be affected . Pleuritis is the most common manifestation of lung disease associated with RA, but this condition often remains asymptomatic . Rheumatoid arthritis‐interstitial lung disease ( RA ‐ ILD ) refers to a diverse range of pulmonary disorders that affect the interstitium of the lung.…”

“…Following immunization with collagen II (CII) in complete Freund's adjuvant (CFA), DBA/1 mice develop arthritis of major joints [1]. This experimental system, called collagen-induced arthritis (CIA), is used as a study model for rheumatoid arthritis asymptomatic [8,9]. Rheumatoid arthritis-interstitial lung disease (RA-ILD) refers to a diverse range of pulmonary disorders that affect the interstitium of the lung.…”

“…Three different interstitial pathologies can be distinguished in RA: (i) bronchiolitis, (ii) usual insterstital pneumonia (UIP), and (iii) rheumatoid nodules . The pathogenesis of extra‐articular complications in RA is incompletely understood and evidence for similar multi‐organ involvement in CIA is scarce and ambiguous . Having shown that IFN‐γ receptor knockout (IFN‐γR KO) mice are more sensitive to induction of CIA , we speculated that they might be more suitable than wild‐type (WT) mice to detect inflammation in other organs.…”